hey my coolant gauge goes all the way to H randomly and goes back down and then floats back up acts retarded basically. when i shut off the car and turn it back on it goes right to the middle normal position so i know my car isn't actually hot. what is causing the gauge to be acting this way?

 

It's more than likely your thermostat, located in the lower rad. hose area. It's either opening up completely or partially or vice versa. That, or its your ECTS, or TEMPERATURE GAUGE sensor, located next to the ECTS. Take a look at the diagram in the Haynes manual to get a good look.

 

your thermostat is stuck shut....replace it to fix...only like $8